I looked through the forums and see that blues juniors are setting their master volumes all the way up and using the volume control as regular volume to get a big clean tone. I've been doing that lately and it sounds pretty good, very close to that punchy fender clean tone I like. I use pedals for my overdriven tones. My question that I couldn't really find an answer to is, does running the master volume always on full, even though my regular volume is usually between 2 and 4, hurt the amp or cut the life on the tubes at all?